Adaptation of Temperate Seagrass to Arctic Light Relies on Seasonal Acclimatization of Carbon Capture and Metabolism

• Published in: Frontiers in Plant Science
• Main Authors: Jueterbock, Alexander, Duarte, Bernardo, Coyer, James, Olsen, Jeanine L., Kopp, Martina Elisabeth Luise, Smolina, Irina, Arnaud-Haond, Sophie, Hu, Zi-Min, Hoarau, Galice
• Other Authors: Nord University Bodø, Universidade de Lisboa = University of Lisbon = Université de Lisbonne (ULISBOA), Marine and Environmental Sciences Centre Portugal (MARE), Instituto Universitário de Ciências Psicológicas, Sociais e da Vida = University Institute of Psychological, Social and Life Sciences (ISPA), University of New Hampshire (UNH), University of Groningen Groningen, MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Qingdao National Laboratory for Marine Science and Technology, Service de bactériologie, parasitologie, virologie et hygiène hospitalière La réunion, Groupe Hospitalier Sud Ile-de-France (GHSIF)-CHR La réunion
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: Survival; Genome; Arctic light; Carbon capture; Daylength; Energy storage; JIP test; Phytochrome C; Requirements; Biomass; Growth; Climate change; Respiration; Photosynthesis; Eelgrass (Zostera marina); Posidonia oceanica; [SDE.MCG]Environmental Sciences/Global Changes; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Arctic; Arctic Population
• Online Access: https://hal.umontpellier.fr/hal-03589731; https://hal.umontpellier.fr/hal-03589731/document; https://hal.umontpellier.fr/hal-03589731/file/fpls-12-745855.pdf; https://doi.org/10.3389/fpls.2021.745855

WOS:000730869600001 International audience Due to rising global surface temperatures, Arctic habitats are becoming thermally suitable for temperate species. Whether a temperate species can immigrate into an ice-free Arctic depends on its ability to tolerate extreme seasonal fluctuations in daylength. Thus, understanding adaptations to polar light conditions can improve the realism of models predicting poleward range expansions in response to climate change. Plant adaptations to polar light have rarely been studied and remain unknown in seagrasses. If these ecosystem engineers can migrate polewards, seagrasses will enrich biodiversity, and carbon capture potential in shallow coastal regions of the Arctic. Eelgrass (Zostera marina) is the most widely distributed seagrass in the northern hemisphere. As the only seagrass species growing as far north as 70 degrees N, it is the most likely candidate to first immigrate into an ice-free Arctic. Here, we describe seasonal (and diurnal) changes in photosynthetic characteristics, and in genome-wide gene expression patterns under strong annual fluctuations of daylength. We compared PAM measurements and RNA-seq data between two populations at the longest and shortest day of the year: (1) a Mediterranean population exposed to moderate annual fluctuations of 10-14 h daylength and (2) an Arctic population exposed to high annual fluctuations of 0-24 h daylength. Most of the gene expression specificities of the Arctic population were found in functions of the organelles (chloroplast and mitochondrion). In winter, Arctic eelgrass conserves energy by repressing respiration and reducing photosynthetic energy fluxes. Although light-reactions, and genes involved in carbon capture and carbon storage were upregulated in summer, enzymes involved in CO2 fixation and chlorophyll-synthesis were upregulated in winter, suggesting that winter metabolism relies not only on stored energy resources but also on active use of dim light conditions. Eelgrass is unable to use excessive amounts of ...